Control knob with multiple degrees of freedom and force feedback

ABSTRACT

The present invention provides a control knob on a device that allows a user to control functions of the device. In one embodiment, the knob is rotatable in a rotary degree of freedom and moveable in at least one transverse direction approximately perpendicular to the axis. An actuator is coupled to the knob to output a force in the rotary degree of freedom about the axis, thus providing force feedback. In a different embodiment, the knob is provided with force feedback in a rotary degree of freedom about an axis and is also moveable in a linear degree of freedom approximately parallel to the axis, allowing the knob to be pushed and/or pulled by the user. The device controlled by the knob can be a variety of types of devices, such as an audio device, video device, etc. The device can also include a display providing an image updated in response to manipulation of the knob. Detent forces can be provided for the knob by overlapping and adjusting ranges of closely-spaced detents in the rotary degree of freedom of the knob.

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation-in-part of co-pending parentpatent application Ser. No. 09/049,155, filed Mar. 26, 1998, entitled,“Force Feedback Mouse Wheel,” and Ser. No. 09/087,022, filed May 29,1998, entitled, “Force Feedback Interface Having Isotonic and IsometricFunctionality”, which is a divisional application of U.S. Pat. No.5,825,308, filed Nov. 26, 1996, all assigned to the assignee of thepresent application, and all of which are incorporated herein byreference.

BACKGROUND OF THE INVENTION

[0002] This invention relates generally to knob control devices, andmore particularly to control knob devices including force feedback andadditional input functionality.

[0003] Control knobs are used for a variety of different functions onmany different types of devices. Often, rotary control knobs offer adegree of control to a user that is not matched in other forms ofcontrol devices, such as button or switch controls. For example, manyusers prefer to use a rotating control knob to adjust the volume ofaudio output from a stereo or other sound output device, since the knoballows both fine and coarse adjustment of volume with relative ease,especially compared to button controls. Both rotary and linear (slider)knobs are used on a variety of other types of devices, such as kitchenand other home appliances, video editing/playback devices, remotecontrols, televisions, etc. Some control knobs have been provided with“force feedback.” Force feedback devices can provide physical sensationsto the user manipulating the knob. Typically, a motor is coupled to theknob and is connected to a controller such as a microprocessor. Themicroprocessor receives sensor signals from the knob and sendsappropriate force feedback control signals to the motor so that themotor provides forces on the knob. In this manner, a variety ofprogrammable feel sensations can be output on the knob, such as detents,spring forces, or the like.

[0004] One problem occurring in control knobs of the prior art is thatthe knobs are limited to basic rotary motion. This limits the controloptions of the user to a simple, one-degree-of-freedom device that doesnot allow a variety of selection options. In additions if force feedbackis provided on the knob, the limited control functionality of the knoblimits the user from fully taking advantage of the force feedback toprovide more control over desired functions.

SUMMARY OF THE INVENTION

[0005] The present invention provides a knob control interface thatallows a user to control functions of a device in a variety of ways.Embodiments of the knob controller include additional degrees of freedomfor the knob and force feedback applied to the knob.

[0006] More particularly, in one embodiment a knob controller device ofthe present invention includes a knob coupled to a grounded surface. Theknob is rotatable in a rotary degree of freedom about an axis extendingthrough the knob, and the knob also moveable in a transverse directionapproximately perpendicular to the axis. A rotational sensor detects aposition of the knob in the rotary degree of freedom, and a transversesensor detects a position of the knob in the transverse direction. Anactuator is coupled to the knob to output a force in the rotary degreeof freedom about the axis, thus providing force feedback. In a preferredembodiment, the knob is moveable in multiple transverse directions. Forexample, the transverse sensor includes a switch that detects when theknob is moved in a transverse direction; the switch can be a hat switchhalving multiple individual switches, for example. In one embodiment,the knob is moveable in four transverse directions spaced approximatelyorthogonal to each other.

[0007] Furthermore, a local microprocessor can be included to controlthe force feedback on the knob. The microprocessor receives sensorsignals from the rotary and transverse sensors and controls a functionof a device in response to the sensor signals. The device can be any ofa variety of electrical or electronic types of devices. The device canalso include a display, wherein an image on said display is changed inresponse to manipulation of the knob in the transverse direction. Amethod of the present invention for controlling functions of a devicefrom input provided by a knob similarly uses sensor signals from arotary sensor and a transverse sensor to control at least one functionof a device, such as adjusting a frequency of a radio tuner or updatinga displayed image based on at least one of the sensor signals.

[0008] In another aspect of the present invention, a knob is coupled toa grounded surface, where the knob is rotatable in a rotary degree offreedom about an axis extending through the knob. The knob is alsomoveable in a linear degree of freedom approximately parallel to theaxis. A rotational sensor and a linear sensor detect positions of theknob in the respective degrees of freedom. An actuator is also coupledto the knob and operative to output a force in the rotary degree offreedom about the axis, thereby providing force feedback to the knob.The linear degree of freedom of the knob allows it to be pushed and/orpulled by the user, where the push or pull motion is detected by thelinear sensor. A spring member is preferably included for biasing theknob to a center position in the linear degree of freedom. The linearsensor can, for example, include a grounded switch that is contacted bya pusher member coupled to the knob when the knob is moved in the lineardegree of freedom. Alternatively, the linear sensor can detect aposition of the knob within a detectable continuous range of motion ofthe knob. The transverse degree of freedom of the previous embodiment ofthe knob can also be included. A microprocessor preferably receives thesensor signals and controls a function of a device in response to thesensor signals, and also sends force feedback signals to the actuator tocontrol forces output by the actuator.

[0009] In a different aspect of the present invention, a method forproviding detent forces for a force feedback control includes outputtinga first force by an actuator on a user manipulatable object, such as arotary knob, for a first detent when the user object is moved within arange of the first detent. The first force assists movement of the userobject toward an origin position of the first detent and resistsmovement away from the origin position. A second force for a seconddetent is also output on the user object when the user object is movedwithin a range of the second detent, similar to the first force. Aportion of the range of the first detent overlaps a portion of the rangeof the second detent. The overlapped portions of the ranges preferablymodifies the second force such that a force at the beginning point ofthe second detent range has less magnitude than a force at an endpointof the second detent range. Preferably, the first force and second forceeach have a magnitude that increases the further that the user object ispositioned from that detent's origin. Preferably, the direction of theknob changes the range endpoint magnitudes Such that if the knob ismoved in the opposite direction, the first-encountered point of thefirst detent range has a lesser magnitude than the last-encounteredpoint.

[0010] In another aspect of the present invention, a method forproviding detent forces for a force feedback control includes defining aperiodic wave and using at least a portion of the periodic wave todefine a detent force curve. The detent force curve defines a force tobe output on a user manipulatable object, such as a rotary knob, basedon a position of the user manipulatable object in a degree of freedom.The detent force curve is then used to command the force on the usermanipulatable object as output by an actuator. The type, period andmagnitude can be specified for the periodic wave. The detent force curvecan be defined by specifying a portion of said periodic wave to be thewidth of the detent force curve, specifying a phase and an offset to beapplied to said periodic wave to define the detent force curve, and/orspecifying an increment distance between successive detents.

[0011] The apparatus and method of the present invention provide ancontrol knob for a device that includes greater control functionalityfor the user. The lineal and transverse degrees of freedom of the knoballow the user to select functions, settings, modes, or options withmuch greater case and without having to take his or her hand off theknob. Force feedback may also be added to the knob to provide the userwith greater control and to inform the user of options and selectionsthrough the sense of touch. Force feedback detent implementations of thepresent invention provide overlapping detent ranges to allow moreaccurate control of a knob by a user within closely-spaced detents, andan efficient, convenient method for defining detents from periodicwaves.

[0012] These and other advantages of the present invention will becomeapparent to those skilled in the art upon a reading of the followingspecification of the invention and a study of the several figures of thedrawing.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013]FIG. 1 is a perspective view of one embodiment of a deviceincluding a control knob of the present invention;

[0014]FIG. 2 is a diagrammatic view of a display allowing the user touse the knob of the present invention to select features of the device;

[0015]FIG. 3a is a perspective view of one embodiment of the mechanismfor implementing the control knob of the present invention;

[0016]FIG. 3b is a side elevational view of the embodiment of FIG. 3a;

[0017]FIG. 4a is a perspective view of a second embodiment of themechanism for implementing the control knob of the present invention;

[0018]FIG. 4b is a top plan view of a unitary plate used in theembodiment of FIG. 4a;

[0019]FIG. 4c is a side elevational view of the embodiment of FIG. 4a;

[0020]FIG. 5 is a perspective view of a linear slider control of thepresent invention;

[0021]FIGS. 6a-6 d illustrate nonoverlapping, overlapping, andhysteresis features of force detent profiles;

[0022]FIGS. 7a-7 e are graphs illustrating the creation of detent forceprofiles from periodic waves according to the present invention; and

[0023]FIG. 8 is a block diagram of a control system for the control knobof the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0024]FIG. 1 is a perspective view of an example of a control panel 12for a device 10 including a control knob of the present invention. Inthe described embodiment, device 10 is an audio device that controls theoutput of sound, such as music or speech, from speakers that areconnected to the device 10. For example, a common embodiment of device10 is a stereo system that includes the ability to play sound from oneor more media or signals, such as cassette tapes, digital audiotransmission (DAT) tapes, compact discs (CD's) or other optical discs,or radio signals transmitted through the air from a broadcastingstation.

[0025] The device 10 can also include additional or other functionalitynot related to audio control and output. For example, many vehiclesinclude electronic systems to control the temperature in the vehiclecabin (air conditioning, heat, etc.), as well as systems to provideinformation on the current operating characteristics of the vehicle,such as current speed, engine temperature, fuel or other fluid levels,whether windows of the vehicle are open, etc. Other systems may includea navigation system that displays a map and the current location of thevehicle with respect to the map, a cellular telephone or other portabletelephone control system, and a security/alarm system. Device 10 caninclude the ability to display information from and/or influence suchother systems in a vehicle or other environment, such as a house,office, etc.

[0026] Alternatively, device 10 can be a variety of other electronic orcomputer devices. For example, device 10 can be a home appliance such asa television set, a microwave oven or other kitchen appliances, a washeror dryer, a home stereo component or system, a home computer, a set topbox for a television, a video game console, a remote control for anydevice, a controller or interface device for a personal computer orconsole games, a home automation system (to control such devices aslights, garage doors, locks, appliances, etc.), a telephone,photocopier, control device for remotely-controlled devices such asmodel vehicles, toys, a video or Film editing or playback system, etc.Device 10 can be physically coupled to the control panel 12, or thepanel 12 can be physically remote from the device 10 and communicatewith the device using signals transferred through wires, cables,wireless transmitter/receiver, etc.

[0027] Device 10 preferably includes a front panel 12, a display 14,several control buttons 16, and one or more control knobs 18 of thepresent invention. Front panel 12 can be mounted, for example, on theinterior of a vehicle, such as on or below the dashboard, or in someother convenient area. Alternatively, the front panel 12 can be thesurface of the external housing of the device 10 itself, such as astereo unit. The device 10 may include several functions, such asplaying an audio track, adjusting volume, tone, or balance of an audiooutput, displaying all image (icons, a map, etc.), or adjusting thetemperature or fan speed in a vehicle, which can be changed or set bythe user manipulating the controls of the device 10 on front panel 12.

[0028] Display 14 is provided to show information to the user regardingthe controlled device or system and/or other systems connected to thedevice 10. For example, options 20 can be displayed to indicate whichfunction of the device 10 is currently selected. Such options caninclude “radio,” “tape,” “CD,”, or power, as shown. Other information,such as the current radio frequency 22 selected for a radio tuner, canalso be displayed. Furthermore, any information related to additionalfunctionality of the device 10 can also be displayed. For example,information 24 can be provided to allow the user to select one or morefunctions not related to the audio operation of the device 10. In someembodiments, a map or similar graphical display can be shown on display14 of all device 10 to allow the user to navigate. Some examples offunctions displayed by a display 14 are shown with respect to FIG. 2,below. In other embodiments, display 14 can be a separate monitordisplaying a graphical user interface or other graphical environment ascontrolled by a host computer. Display 14 can be any suitable displaydevice, such as an LED display, LCD display, gas plasma display, CRT, orother device. In some embodiments, display 14 can include atouch-sensitive surface to allow a user to touch displayed imagesdirectly on the display 14 to select those images and an associatedsetting or function.

[0029] Control buttons 16 are often provided on device 10 to allow theuser to select different functions or settings of the device. Forexample, on an audio device, buttons 16 can include radio station presetbuttons, rewind/fast forward tape functions, power, speaker loudness,etc. Virtually any function of the device can be assigned to buttons 16.The buttons 16 may also be used in conjunction with the control knobs18, as described below.

[0030] Control knobs 18 are provided to allow the user a different typeof control of functions and settings of device 1I than the buttons 16allow. Knobs 18, in the described embodiment, are approximatelycylindrical objects engageable by the user. The knobs 18 canalternatively be implemented as a variety of different objects,including conical shapes, spherical shapes, dials, cubical shapes, rods,etc., and may have a variety of different textures on theircircumferential surfaces, including bumps, lines, or other gripe, oreven projections or members extending from the circumferential surface.In addition, any of variety of differently-sized knobs can be provided;for example, if high-magnitude forces are output, a larger-diametercylindrical knob is often easier for a user to interface with device 10.In the described embodiment, each knob 18 rotates in a single rotarydegree of freedom about an axis extending out of the knob, such as axisA. The user preferably grips or contacts the circumferential surface 26of the knob 18 and rotates it a desired amount. Force feedback can beprovided in this rotary degree of freedom in some embodiments, asdescribed in greater detail with reference to FIGS. 3a and 3 b.

[0031] Furthermore, the control knobs 18 of the present invention allowadditional control functionality for the user. The knobs 18 arepreferably able to be moved by the user in one or more directionsapproximately perpendicular to the axis A of rotation, e.g. parallel tothe surface of the front panel 12 as shown in FIG. 1 (“transversemotion” or “transverse direction”). This transverse motion is indicatedby arrows 28. For example, the knob 18 can be moved in the fourorthogonal directions shown, or may be moveable in less or moredirections in other embodiments, e.g. only two of the directions shown,or in eight directions spaced at 45 degree intervals about axis A. Inone embodiment, each transverse direction of the knob is spring loadedsuch that, after being moved in a direction 28 and once the userreleases or stops exerting sufficient force on the knob, the knob willmove back to its centered rest position. In other embodiments, the knobcan be provided without such a spring bias so that the knob 18 stays inany position to which it is moved until the user actively moves it to anew position.

[0032] This transverse motion of knob 18 can allow the user to selectadditional settings or functions of the device 10. In some embodiments,the additional control options provided by knob 18 allow the number ofbuttons 16 and other controls to be reduced, since the functionsnormally assigned to these buttons can be assigned to the knob 18. Forexample, the user can move a cursor 30 or other visual indicator ondisplay 14 (e.g. pointer, selection box, arrow, or highlighting ofselected text/image) to a desired selection on the display. Thus, thecursor 30 can be moved from the “radio” selection shown to the “tape”selection by moving the knob 28 in the down direction as shown inFIG. 1. Or, the cursor 30 can be moved to the “CD” selection by movingthe knob 28 in the direction to the right. If knob 18 is provided withdiagonal directions (e.g. at 45 degree intervals), the user can move thecursor 30 from the “radio” selection directly to the “off” selection.The user can similarly move cursor 30 or a different indicator to theother information settings 24, to the frequency display 22, or to anyother displayed option, setting, or area/region on the display 14.

[0033] Besides such a cursor positioning mode, the transverse motion ofknob 28 can also directly control values or magnitudes of settings. Forexample, the left motion of knob 18 can decrease the radio stationfrequency value 22, where the value can (decrease at a predeterminedrate if the user continually holds the knob 18 in the left direction.The right motion of the knob 18 can similarly increase the frequencyvalue 22. In another example, once one of the information settings 24 isselected, a sub menu can be displayed and the directions 28 of knob 18can adjust air temperature, a timer, a cursor on a displayed map, etc.

[0034] Different modes can also be implemented; for example, the defaultmode allows the user to control cursor 30 using the directions 28 of theknob. Once the cursor is located at a desired setting, such as thefrequency value 22, the user can switch the mode to allow the directions28 to control the setting itself, such as adjusting the value 22. Toswitch modes, any suitable control can be used. For example, the usercan push a button, such as button 29, to toggle a mode. Alternatively,the user can push or pull the knob 18 to select the mode; thisfunctionality of the present invention is described below. Or, some orall of the directions 28 can be used to select modes; for example, thedown direction might switch to “volume” mode to allow the user to rotatethe knob to adjust volume; the up direction can switch to “adjust radiofrequency” mode, and the left direction can switch to “balance” mode(for adjusting the speaker stereo balance for audio output with rotationof knob 18).

[0035] In addition, the control knobs 18 are preferably able to bepushed and/or pulled in a degree of freedom along axis A (orapproximately parallel to axis A). This provides the user withadditional ways to select functions or settings without having to removehis or her grip From the knob. For example, in one preferred embodiment,the user can move cursor 30 or other indicator on the display 14 usingthe directions 28 of the knob 18; when the cursor has been moved to adesired setting or area on the display, the user can push the knob 18 toselect the desired setting, much like a mouse button selects all icon ina graphical user interface of a computer. Or, the push or pull functioncan be useful to control the modes discussed above, since the user cansimply push the knob and rotate or move the knob while it is in thepushed mode, then release or move back the knob to select the othermode. The modes discussed above can also be toggled by pushing orpulling the knob 18. The push and/or pull functionality of the knob 18can be provided with a spring return bias, so that the knob returns toits rest position after the use releases the knob. Alternatively, theknob can be implemented to remain at a pushed or pulled position untilthe user actively moves the knob to a new position.

[0036] A slider control 32 of the present invention may also be includedin device 10. Slider control 32 includes a slider knob 34 which isgrasped by the user and moved in a linear direction as shown by arrow36. In the present invention, slider control 32 preferably includesforce feedback functionality. Thus, as the user moves the knob 34, forcesensations such as a spring force, a damping force, jolts, detents,textures, or other forces can be output and felt by the user.Furthermore, the slider knob 34 can include a button 38 which can bepressed by the user similarly to the push knob embodiment discussedabove with reference to knob 18. Alternatively, the knob 34 can bepushed and/or pulled similarly to the knob 18 as described above. Slidercontrol 32 can control any of the various functions, settings, oroptions of the device 10. For example, the motion left or right of knob34 can control the radio frequency 22, where force detents are outputfor each station and/or each preset station previously programmed by theuser. Or, the cursor 30 can be moved using the slider knob 34, such thatwhen the cursor reaches a desired setting or selection, the user canpush button 38 or push on the knob 34 to select that setting. Otherfunctions such as volume, balance, tone, map functions, temperaturefunctions, or mode selection can also be controlled by the slidercontrol 32. Slider control is described in greater detail with respectto FIG. 5.

[0037]FIG. 2 is an example showing images which can be displayed ondisplay 14 to assist the user in selecting options with knobs 18 and/orslider control 32. Display 14 can present icons as shown, in thisexample for the control of audio output signals from device 10. Icon 46is selected to control the volume of the audio output using knob 18,where the circular pointer 42 can be moved in accordance with the knob18. Icon 47 is used to control the frequency of the radio tuner (thecurrent selected frequency can be displayed as well), and the icons 48,49, and 51 are used to control the balance, treble, and bass of theaudio, respectively. For example, the indicator 44 can be moved left orright depending on the current setting. Cursor 45 is used to select oneof the icons to allow the control of the functions associated with theselected icon. Cursor 45 indicates which of the icons in display 14 arecurrently selected. The icon can be moved from each icon to the next byrotating the knob 18. Alternatively, the transverse motion of the knobcan move the cursor 45. A function of the device designed by theselected icon can be selected by pushing the knob 18 in the lineardirection. The cursor can be a square or other-shaped box, or thecurrently-selected icon can be highlighted to indicate the cursor'slocation.

[0038] It should be noted that each of the icons can preferably be setto a position control mode or to a rate control mode as desired by theuser. For example, the user may select position control for volume 46and rate control for the functions of icons 47, 48, 49, and 51, or anyother combination. In position control mode, force detents arepreferably output to indicate particular settings or how far the knob 18has been rotated. In rite control mode, detents can also be output. Forexample, the user maintains the knob 18 at a rotary position away fromthe center position in opposition to a spring return force, and a detentforce (e.g., jolt) is output to indicate how much a particular value hasbeen changed. For example, a jolt can be output for each 10 MHz offrequency that is increased, or for each particular amount of treble orbass that has been adjusted.

[0039] Other icons can be displayed in other embodiments. For example,an for vent location can be selected using cursor 45 to determine whichvents in the car provide air flow, where a top vent, a bottom vent, orboth top and bottom vents can be selected. A fan speed icon can beselected to choose a fan speed setting for the air flow from the ventsin the car. In a preferred force feedback implementation, once the fanspeed icon has been selected by pushing in the knob 18, the user mayrotate the knob 18 to select the fan rotation speed in a positioncontrol mode. A small vibration can be output on the knob 18 in therotary degree of freedom, where the frequency (or magnitude) of thevibration forces correlate with the magnitude of fan rotation speed,i.e., a high fan speed provides a fast vibration. Furthermore, detentsare preferably output superimposed on the vibration forces so that theuser can feel the fan settings at the detents. This allows the user toselect fan speed based purely on tactile feel, so that the driver neednot look at the display 14. A temperature icon can be selected to adjustthe temperature in the car. The temperature can preferably be adjustedby rotating knob 18, where force detents indicate each temperaturesetting. Icons for moving mechanical components, such as seats ormirrors, can be provided, where a rate control force mode is used tocontrol the position of the components.

[0040]FIG. 3a is a perspective view and FIG. 3b is a side elevationalview of one implementation of control knob 18 of the present invention.In this implementation, knob 18 includes the ability to movetransversely in four directions, and the knob 18 can also be pushed foradditional selection ability.

[0041] Knob 18 is rigidly coupled to a rotatable shaft 50 which extendsthrough the grounded front panel 12 (shown in dashed lines). Shaft 50extends through a four-way switch 52 which detects the transverse motionof the knob 18 in directions 28. The knob 18 is biased toward thecentered rest position within switch 52 by a spring member 64, describedin greater detail below. When the shaft 50 is moved in any of theprovided transverse directions, a corresponding micro switch (not shown)included on the interior sidewall of the four-way switch 52 is closed,thus causing a signal to be output on leads 54. Thus, switch 52preferably includes individual micro switches, one for each providedtransverse direction (four individual switches in the describedembodiment). A suitable switch for use as switch 52 is a “hat switch”which is commonly provided for analog joystick controllers for personalcomputers and allows 4 or 8 directions to a moveable member. Forexample, joystick hat switches manufactured by such companies as CHProducts, Inc. or Logitech can be used. In other embodiments, two-way,eight-way, or other types of switches can be used, depending on how manydirections are desired.

[0042] A pusher member 56 is rigidly coupled to shaft 50 next to theswitch 52. Since the switch 52 includes an aperture through which theshaft 50 extends, the knob 18, shift 50 and pusher member 56 areoperative to move as a unit along axis A with respect to the front panel(ground) and the switch 52. A switch 58 (see FIG. 3b) is coupled to agrounded member 60 and is provided in the path of the pusher member 56.Thus, when the knob 18 is pushed by the user, the shaft 50 and thepusher member 56 are moved along axis A in a direction indicated byarrow 62 (see FIG. 3b). This causes pusher member 56 to engage thebutton 64 of the switch 58, causing the button 64 to be pushed inwardand close (or open) the switch. The pushing motion of the knob 18 isthus sensed.

[0043] In other embodiments, a sensor can be provided to sense a rangeof positions of the knob 18 or a continuous motion of the knob 18linearly along axis A. For example, a Hall effect switch can be providedon pusher member 56 which measures the position of the pusher member 56relative to a grounded magnet on member 60 (or the Hall effect switchcan be placed on the member 60 and the magnet can be placed on themember 56). Or, an optical sensor (such as a photodiode) or other typeof sensor can detect the position of the member 56 and/or knob 18. Insuch an embodiment, the position of the knob along axis A canproportionately control a function or setting of the device 10. Forexample, such movement can control the volume of audio output of thedevice, motion of a cursor across a display, or the brightness of lightsinside a vehicle.

[0044] A pull switch can be implemented similarly to the push switchshown in FIGS. 3a and 3 b. For example, a switch similar to switch 58can be grounded and provided on the opposite side of pushed member 56 sothat when knob 18 is pulled in a direction opposited to direction 62, abutton on this switch is engaged by the pusher member to detect thepulled motion. The pull motion of knob 18 can also be sensed in acontinuous range similar to the push embodiments described above. Insome embodiments, both push and pull motions of the knob 18 may beprovided and sensed.

[0045] A spring member 64 is rigidly coupled to the pushing member 56 atone end and is rigidly coupled to a rotatable end member 66 at its otherend. Spring member 64 is compressed when the knob 18 and pusher member56 are moved in the direction of arrow 62. Spring member 64 thusprovides a spring force that biases the knob 18 in the directionopposite to direction 62. If the knob 18 is not forced in direction 62,the spring bias moves the knob 18 opposite to direction 62 until theknob reaches its rest position. In those embodiments including a pullmotion of the knob 18 in the direction opposite to direction 62, aspring member can be included on the opposite side of pusher member 56to spring member 64, to bias the knob 18 in direction 62 after the userhas pulled the knob. In yet other embodiments, no spring member 64 isprovided, and the knob 18 remains at any pushed or pulled position untilactively moved to a new position by the user.

[0046] Spring member 64 also provides the transverse motion of knob 18in the directions 28. The flexure of the spring element allows the knobto move in transverse degrees of freedom, while still being relativelytorsionally stiff to allow forces to be transmitted effectively from anactuator to the knob 18 about axis A. In other embodiments, other typesof couplings can be provided to allow a pivot or translational motion inthe directions 28. For example, flexible disc servo couplings orone-piece flexible shaft disc couplings can be provided; such couplingsare available from Renbrandt, Inc. of Boston, Mass. and Helical ProductsCompany, Inc. of Santa Maria, Calif. In other embodiments, bent spaceframes provided in a square-plate coupling or a rectangular coupling canbe used. Furthermore, a different alternate flexible coupling embodimentis described in greater detail with respect to FIGS. 4a-4 c.

[0047] End member 66 is coupled to a rotatable shaft 68 of an actuator70. The housing 72 of actuator 70 is rigidly coupled to grounded member74, and the shaft 68 rotates with respect to the housing 72 and themember 74. Actuator 72 can be controlled to output force on rotatingshaft 68 about axis A, thus driving the shaft and all components rigidlycoupled to the shaft about axis A. The shaft 68 thus rotates end member66, spring member 64, pusher member 56, shaft 50, and knob 18. Theoutput force on knob 18 is felt by the user as force feedback. Actuator70 can be any of a variety of different types of actuators, including aDC motor, voice coil, pneumatic or hydraulic actuator, magnetic particlebrake, etc. A sensor 76 has a shaft rigidly coupled to the rotatingshaft 68 of the actuator 70 and thus detects the rotation of the shaft68 and the knob 18 about axis A. Sensor 76 is preferably a digitaloptical encoder but can alternatively be a different type of sensor,such as an analog potentiometer, a photodiode sensor, a Hall effectsensor, etc.

[0048] The force feedback output on knob 18 can include a variety ofdifferent force sensations. The force feedback can be integrallyimplemented with the control functions performed by the knob. A basicforce sensation is force detents that are output at particularrotational positions of the knob to inform the user how much the knobhas rotated and/or to designate a particular position of the knob. Theforce detents can be simple jolts or bump forces to indicate thedetent's position, or the detents can include forces that attract theknob to the particular rotational detent position and resist movement ofthe knob away from that position. The position can correspond to aparticular radio station frequency or other station (e.g., televisionstation frequency), thus making selection easier for the user. Suchdetents can be provided for additional functions, such as volume controlfor sound speakers, fast forward or rewind of a video cassete recorderor computer-displayed movie (such as a DVD movie), scrolling a displayeddocument or web page, etc. Force feedback “snap-to” detents can also beprovided, for example, for the favorite station frequenciespreprogrammed by the user, where a small force biases the knob to thedetent position when it is just outside the position.

[0049] Also, the magnitude of the force detents can differ based on thevalue being controlled. For example, a radio frequency having a highervalue might be associated with a stronger force detent, while a lowerradio frequency might be associated with a weaker force detent when itis displayed, thus informing the user generally of the radio stationbeing displayed without requiring the user to look at the display 14(which is particularly useful when operating the device 10 whileperforming another task, such as driving a vehicle). In someembodiments, the user can also change the magnitude of detentsassociated with particular values, such as radio stations, to preferredvalues so as to “mark” favorite settings. Programmability of thelocation of the detents in the rotary degree of freedom is alsoconvenient since preferred radio frequencies are most likely spaced atirregular intervals in the radio frequency range, and the ability toprogram the detents at any location in the range allows the user to setdetents to those preferred stations. In addition, the knob can be movedby the actuator 70 to select the nearest preprogrammed station orpreferred setting. Also, different sets of detent force profiles can bestored in a memory device on the device 30 and a particular set can beprovided on the knob 18 by a microprocessor or other controller in thedevice 30.

[0050] Another type of force sensation that can be output on knob 18 isa spring force. The spring force can provide resistance to rotationalmovement of the knob ill either direction to simulate a physical springon the knob. This can be used, for example, to “snap back” the knob toits rest or center position after the user lets go of the knob, e.g.once the knob is rotated past a particular position, a function isselected, and the user releases the knob to let the knob move back toits original position. A damping force sensation can also be provided onknob 18 to slow down the rotation of the knob, allowing more accuratecontrol by the user. Furthermore, any of these force sensations can becombined togther for a single knob 18 to provide multiple simultaneousForce effects.

[0051] The spring return force provided in the rotary degree of freedomof the knob 18 can also be used to implement a rate control paradigm.“Rate control” is the control of a rate of a function, object, orsetting based on the displacement of the knob 18 from a designatedorigin position. The further the knob is moved away from the originposition, the greater the rate of change of controlled input. Forexample, if a rate control knob 18 with a spring return force is used tocontrol the radio frequency, then the further the knob is moved from thecenter origin position, the faster the radio frequency will change inthe appropriate direction. The frequency stops changing when the knob isreturned to the origin position. The spring force is provided so thatthe further the user moves the knob away from the origin position, thegreater the force on the knob in the direction toward the originposition. This feels to the user as if he or she is inputting pressureor force against the spring rather than rotation or displacement, wherethe magnitude of pressure dictates the magnitude of the rate. However,the amount of rotation of the knob is actually measured and correspondsto the pressure the user is applying against the spring force. Thedisplacement is thus used as an indication of input force.

[0052] This rate control paradigm differs from the standard knob controlparadigm, which is known as “position control”, i.e. where the input isdirectly correlated to the position of the knob in the rotary degree offreedom. For example, in the radio frequency example, if the user movesthe knob to a particular position, the radio frequency is changed to aparticular value corresponding to the rotary position of the knob. Forcedetents are more appropriate for such a paradigm. In contrast, in therate control example, moving the knob to a particular position causesthe radio frequency to continue changing at a rate designated by theposition of the knob.

[0053] Since the spring force and detent forces are programmable and canbe output as directed by a microprocessor or other controller, a singleknob 18 can provide both rate control and position control overfunctions or graphical objects. For example, a mode selector, such as abutton or the push/pull knob motion, can select whether rate control orposition control is used. One example of a force feedback deviceproviding both rate control (isometric input) and position control(isotonic input) is described in greater detail in co-pending patentapplication Ser. No. 08/756,745, filed Nov. 26, 1996, and incorporatedherein by reference. Such rate control and position control can beprovided in the rotary degree of freedom of the knob 18. Also, if knob18 is provided with force feedback in the transverse degrees of freedomor in the push/pull linear degree of freedom, then the rate control andposition control modes can be provided in those degrees of freedom.

[0054] Other force sensations that can be output on knob 18 includeforces that simulate ends of travel for the knob 18 or inform the userthat the end of travel has been reached. For example, as the userrotates the knob in one direction to adjust the radio frequency 22, theend of the radio frequency range is reached. There is no hard stop onthe knob 18 at this position, but the actuator 70 can be controlled tooutput an obstruction force to prevent or hinder the user from rotatingthe knob further in that direction. Alternatively, a jolt force can beoutput that is stronger in magnitude than normal detents, which informsthe user that the end of the frequency range has been reached. The usercan then continue to rotate the knob in that direction, where thedisplayed frequency 22 wraps around to the beginning value in the range.

[0055] In another alternate embodiment, one or more of the transversemotions of knob 18 in directions 28 can be actuated. For example, agreater range of motion can be provided for each transverse direction ofthe knob than typically allowed by a hat switch, and a linear or rotaryactuator can be provided to output forces in the transverse degree offreedom, in one or both directions (toward the center position and awayfrom the center position of the knob). For example, one or more magneticactuators or solenoids can be used to provide forces in these transversedirections.

[0056] Furthermore, in other embodiments, the pull and/or push motion ofknob 18 along axis A can be actuated. For example, a jolt force can beoutput on the knob in the linear degree of freedom along axis A as theuser pushes the knob. Also, the spring return force provided by springmember 64 can instead be output using an actuator controlled by amicroprocessor.

[0057] It should be noted that the embodiment of FIGS. 3a and 3 b is notthe only embodiment of the present invention. For example, someembodiments may only include the transverse motion of knob 18 and notthe push and/or pull functionality nor the force feedback functionality.Other embodiments may only include the push and/or pull functions. Yetother embodiments may only include force feedback with transverse knobmotion, or force feedback with push and/or pull functions.

[0058]FIG. 4a is a perspective view of an alternate embodiment 80 of thecontrol knob 18 of the present invention. In embodiment 80, knob 18 iscoupled to shaft 50, which is rigidly coupled to a flex member 82. Flexmember 82 includes a base plate 84 and a plurality of bent portions 86extending from the base plate 84. For example, as shown in FIG. 4b, theflex member 82 can be formed by cutting out the circular base plate 84and the portions 86 from a unitary piece 85 of material, such as springsteel or stainless steel. The unitary piece is preferably provided as athin sheet. Holes 88 or other apertures can be placed near the ends ofthe portions 86. Referring back to FIG. 4a, the portions 86 are thenbent such that the holes 88 substantially align with the other holes 88,where the holes 88 are aligned with axis B that extends approximatelyperpendicular to the surface of the base plate 84. The base plate 84 isrigidly coupled to the rotating shaft of the actuator 70.

[0059]FIG. 4c is a side elevational view of the embodiment 80 of FIG.4a. In the described embodiment, knob 18 is coupled to shaft 50, whichextends through a switch 90 and is coupled to the bent portions 86 ofthe flex member 82. The switch 90 is preferably similar to the switch 52described above with reference to FIGS. 3a and 3 b. For example, amicroswitch can be provided on the inside surface of the housing ofswitch 90 for each transverse direction of knob 18 that is to be sensed.The base plate 84 of the flex member 82 is rigidly coupled to shaft 92of actuator 70. The shaft 92 is rigidly coupled to a shaft (not shown)of sensor 76, which has a grounded housing that is coupled to thegrounded housing of actuator 70.

[0060] Alternatively, a plurality of sensors can be positioned externalto the flex member 82 instead of using switch 90. For example, switches94 can be positioned on two or more sides around the flex member 82,depending on how many directions are to be sensed. Switches 94 can becontact switches that each detect when the portions 86 move to engagethe contact switch, thus indicating movement of knob 18 in a particulartransverse direction. Alternatively, members can be positioned on shaft50 which extend to the sides of the shaft and which engage electricalcontacts or other sensors. In other embodiments, other switches orsensors can be used, as described above in the embodiment of FIG. 3a. Aspring (not shown) can also be coupled to the shaft 50, flex member 82,or knob 18 to provide linear motion along the axis B and allow the knob18 to be pushed and/or pulled by the user, as described in theembodiment of FIG. 3a. Some types of flexible couplings that allowtransverse motion of the knob 18 may also allow linear motion along axisB, such as flexible disc servo couplings, in which case such as springmay not be needed.

[0061] In operation, the transverse motion of knob 18 in embodiment 80operates as follows. The knob 18 is moved by the user approximately in atransverse direction 28, which causes the shaft 50 to move with the knobby pivoting approximately about the end of the shaft 50 where it iscoupled to the portions 86. Shaft 50 is allowed such movement due to theflexibility in portions 86. In some embodiments, the knob 18 is alsoallowed to translate in a transverse direction 28 as well as or inaddition to pivoting approximately in directions 28. When the knob 18 isrotated about axis B (by the user or the actuator), the shaft 50 rotatesabout its lengthwise axis, causing the flex member 82 to rotate aboutaxis B. Since the portions 86 are stiff in the rotational directionabout axis B, torque output on the shaft 50 and on the flex member 82 istransmitted accurately from actuator 70 to knob 18 and from knob 18 tosensor 76. Thus, the rotation on flex member 92 causes the shaft 92 torotate, which is sensed by sensor 76. The rotational force about axis Boutput by actuator 70 is similarly transmitted from shaft 92, throughflex member 82, to shaft 50 and knob 18.

[0062]FIG. 5 is a perspective view of an exemplary embodiment for theslider control 32 as shown in FIG. 1. Slider control 32 includes sliderknob 34 which may move in a linear degree of freedom as indicated byarrow 36. In the described embodiment, a transmission member 100 isrigidly coupled to the knob 34 and extends through a slit or opening 102in the front panel 12 or other grounded member. Transmission member 100can be coupled to an actuator, such as linear voice coil actuator 104.

[0063] The member 100 can move in and out of a housing 101 of actuator104 as indicated by arrow 103. The housing 101 preferably includes acentral core 107 and a number of elongated magnets 109. An armature 105includes a hollow, cylindrical member having an inner surface whichslidingly engages the core 107. Wrapped around the armature 105 arecoils 110 that are electrically coupled to actuator and/or sensorinterfaces. The armature 105 is coupled to the transmission member 100so that the armature 105 and member 100 can move in a linear fashion asindicated at arrow 103. Other voice coil configurations can also beused, such as differently shaped cores, different coil layouts, etc.Voice coil actuator 104 can serve both as a sensor and an actuator.Alternatively, the voice coil can be used only as an actuator, and aseparate sensor 106 can be used. Separate sensor 106 can be a linearsensor that senses the motion or position of an extension 112 that iscoupled to the transmission member 100 and moves linearly when thetransmission member moves. Voice coil actuators such as actuator 104 aredescribed in greater detail in U.S. Pat. No. 5,805,140, the disclosureof which is incorporated herein by reference. In particular, theoperation of the voice coils as actuators and/or sensors is describedtherein.

[0064] Other types of actuators 104 and transmissions can also be usedin slider control 32. For example, a capstan drive and cabletransmission can provide linear forces on the knob 34. Other types ofactuators suitable for use with the slider include active actuators,such as linear current control motors, stepper motors,pneumatic/hydraulic active actuators, a torquer, etc. Passive actuatorsmay also be used, such as magnetic particle brakes, friction brakes,fluid controlled passive actuators, or other actuators which generate adamping resistance or friction in a degree of motion.

[0065] Slider knob 34 can also include a button 38 which is used toprovide input to the device 10. In yet other embodiments, the sliderknob 34 can be pushed and/or pulled in a linear degree of freedomapproximately perpendicularly to the surface of front panel 12. In suchan embodiment, a moveable contact switch can be provided between theknob 34 and the transmission member 100. A spring member can also beprovided similarly to the embodiment of FIGS. 3a-3 b and 4 a-4 c to biasthe knob 34 to a neutral rest position.

[0066] The force sensations and modes described above for the rotaryknob in FIGS. 3a-3 b and 4 a-4 c may also be used for the slider control32 in a linear degree of freedom. For example, force detents can beapplied in a position control paradigm as the knob 34 is moved in itslinear degree of freedom. In a rate control paradigm, a spring returnforce can bias the knob 34 toward a center origin position, for examplethe center of the range of motion of the knob. The further the usermoves the knob from the origin position, the greater the spring forceopposing that motion and the greater the rate of the controlled valuechanges (increases or decreases). Other force effects include dampingforces, texture forces, jolts, obstruction forces, assistive forces,periodic forces such as vibration forces, and end-of-travel forces.

[0067]FIGS. 6a and 6 b are diagrammatic illustrations illustratingdetent force profiles suitable for use with the knobs of device 10.Detent force profiles can be implemented by a microprocessor or othercontroller based on instructions stored in a computer readable medium,such as a memory circuit, magnetic disk, optical disk, etc. In FIG. 6a,a detent force profile is shown. The vertical axis F represents themagnitude of force output, where a positive F value indicates force inone direction, and a negative F value indicates force in the oppositedirection. The horizontal axis d represents the distance or position ofthe moved user object (knob) in a degree of freedom, where the originposition O indicates the position of the detent, a positive d is aposition past the origin of the detent in one direction, and a negatived is a position past the origin of the detent in the opposite direction.The curve 124 represents the force output for a single detent over aposition range for the detent. Thus, for example, if the user moves theknob clockwise toward the detent origin O1, the motion may be from theleft toward the origin O1 on the axis d. A force toward the origin isoutput at position P1 at a magnitude -M to assist the user in moving theknob clockwise toward the origin. As the user continues to move the knobclockwise toward the origin O1, the assisting force is decreased inmagnitude until no force is output when the knob is positioned at theorigin position. If the user moves the knob counterclockwise from theorigin position O1 (from right to left), the force will resist suchmotion in an increasing manner until the knob has been moved to positionP1, after which the force magnitude drops to zero. Similarly, on thepositive side of the d axis, if the user rotates the knob clockwise awayfrom the detent origin position O1 (corresponding to movement from leftto right), an increasing magnitude of force is output until the knobreaches the position P2, at which point the force magnitude drops fromits maximum at M to zero. If the user moves the knob counterclockwisefrom position P2 toward the origin O1, the user initially feels a largemagnitude force assisting that movement, after which the assisting forcegradually decreases until it is zero at the origin O1. Preferably, pointP1 is at an equal distance from origin O1 as point P2.

[0068] Additional detents may be positioned in the degree of freedom ofthe knob in successive positions, represented along axis d. For example,curve 126 represents another detent that is encountered shortly afterleaving the previous detent curve 124 when turning the knob in aparticular direction.

[0069] A problem occurring with closely spaced detents is that often theuser moves the knob from a first detent to a second detent butunintentionally moves the knob past the second detent due to theassistive detent forces of the second detent. This is because the forcefrom the user required to move the knob past the resistive force of thefirst detent curve is combined with the assistive force of the seconddetent curve, causing the knob to unintentionally move past the secondorigin and past the endpoint of the second detent curve. Furthermore,the same problem occurs when the user moves the knob in the oppositedirection, from the second detent to the first detent. The user mustexert force to overcome the resistance at the last point of the seconddetent curve, which causes the knob to quickly move past the first pointof the first detent curve, where the assistive force is added to themotion to cause the knob to unintentionally move past the lastencountered point of the first detent.

[0070]FIG. 6b shows a detent force profile of the present invention inwhich the detent forces of two successive detents are partiallyoverlapped due to the detents, and provide a hysteresis-like forceeffect. The two detent curves 128 and 130 are identical, thus allowing asingle force command to create the multiple detents if desired. Endpoint131 of curve 128 is positioned at position P1 and endpoint 132 of curve128 is positioned at position P2, where P2 is about the same distancefrom origin O1 as P1. Similarly, endpoint 134 of curve 130 is positionedat position P3 and endpoint 133 of curve 130 is positioned at positionP4, where P4 is about the same distance from origin O2 as P3. Detentcurve 128 ends at endpoint 132 on the right side of origin O1 and withinthe range of forces of detent curve 130. Preferably, the end point 132of curve 128 is positioned well after the endpoint 134 of curve 130,such that the point 132 has a position in the middle of the rangebetween point 134 and the origin O2. The overlapped zone is betweenpositions P3 and P2. In addition, the end point 132 of the first detentpreferably does not extend past the origin O2 of the second detent intothe positive side of the second detent. If another detent is positionedfurther on the d axis after curve 130, the end point 133 of curve 130preferably is positioned well after the starting endpoint of the nextdetent curve and not past the origin of the next detent curve. Similarpositioning can be provided for curves before curve 128 on axis d.

[0071] To solve the problem of unintentionally moving past a successivedetent, the range of the second or successive detent is adjusted suchthat a lesser magnitude is preferably output at the beginning of thesuccessive detent than would normally be output if the entire curve ofthe successive detent were used. Furthermore, the force detent curveused to output force is preferably different depending on the directionof the knob, similar to a hysteresis effect. As shown in FIG. 6c, whenmoving the knob so the knob position changes from left to right, theforce at the beginning of the range of detent curve 130 is at point 135having a magnitude of 0.5M, which is one-half the magnitude M of theforce at the other endpoint 133 of the range of curve 130 (ignoring thesigns or direction of the forces). Of course, in other embodiments point135 can have a magnitude of other fractions of M, such as one-third orthree-fourths of M. Additional curve 127 can be similarly positioned andprovide a similar overlap with curve 130, and additional curves may beadded before curve 128 and/or after curve 127.

[0072] As shown in FIG. 6d, when moving the knob in the other directionso the knob position changes from right to left, the endpoints of thecurve 130 reverse in magnitude with respect to the endpoints shown inFIG. 6c. In FIG. 6d, starting from origin O2, the force at the beginningof the range of detent curve 128 is at point 136 having a magnitude of0.5M, which is one-half the magnitude M of the force at the otherendpoint 131 of curve 128 (other fractions of M can be provided forendpoint 136 in other embodiments). Any additional curves, such as curve127, can be provided with a similar overlap. The force output on theknob thus changes depending on the direction of the knob. In a digitalsensing system (e.g. using a digital encoder), the direction can bedetermined from a history of sensed values. For example, one or moresensed position values can be stored and compared to a current sensedposition to determine the knob direction.

[0073] The use of a lesser magnitude at the beginning of the seconddetent reduces the tendency of the user to unintentionally skip past asecond detent after moving the knob over a first detent closely spacedto the second detent. For example, when moving the knob left to right(e.g., clockwise) from position P1, a first detent (curve 128) ends atpoint 132 of curve 128, after which the force magnitude of point 135 oncurve 130 begins assisting the knob's movement. This magnitude is lessthan the magnitude of the “original” beginning point 134, i.e. thebeginning point of the full curve 130. Thus, less force is assisting theuser to move toward the origin O2 of curve 130 than if the forcemagnitude for beginning point 134 of the curve 130 were in effect. Withless force assisting motion toward origin O2, the user has an easiertime slowing down the knob and preventing the knob from unintentionallyovershooting the origin O2. Furthermore, the changing of endpoints ofthe detent curve, as dependent on direction, provides a hysteresis-likeeffect the reduces the unintentional skip in both directions. Thus, whenmoving the knob from right to left (e.g., counterclockwise) starting atorigin O2, a first detent (curve 130) ends at point 134 of curve 130,after which a magnitude of point 136 on curve 128 begins assisting theknob's movement. This magnitude is less than the magnitude of the“original” beginning point 134. Thus, less force is assisting the userto move toward the origin O1 of curve 128 than if the force magnitudefor beginning point 132 of the curve 128 were in effect. With less forceassisting motion toward origin O1, the user has an easier time slowingdown the knob and preventing the knob from unintentionally overshootingthe origin O1.

[0074] The same overlapping and hysteresis feature can be provided fordifferently-shaped detents as well, such as curved detents of FIGS. 7a-7e, detents having deadbands around the origin O, and/or other-shapedforce profiles. In embodiments having detent endpoints that are spacedfurther apart, or which have very gradually-sloping curves, the overlapand hysteresis may not be needed since there may be enough space in thedegree of freedom for the user to control the knob from unintentionallymoving past the next detent.

[0075]FIG. 7a is a graph illustration 137 of a periodic wave 139 thatcan be used to provide a variety of detent force sensations for use withthe knob control device of the present invention. The periodic waverepresents force exerted on the knob (axis F) vs. the position ordisplacement (axis d) of the knob, similar to the force detent profileshown in FIGS. 6a and 6 b. The wave 139 is a periodic function, such asa sine wave, triangle wave, square wave, etc. In FIG. 7a, a sine waveshape is shown. In the present invention, a portion of the wave may beused to provide detent and other force sensations for the knob 18 or 34.Various parameters of the sine wave are shown in FIG. 7a, includingperiod and magnitude.

[0076] Curve 138 (solid line) represents a detent force effect that hasbeen created based on the sine wave 139. Curve 138 has a width, which isthe amount of the wave 139 along axis d used for the force detent. Thelocation of the detent is the position in the degree of freedom at whichthe detent force is centered, i.e. the location of the origin position Oof the detent. A deadband can be defined to be a distance from theorigin O to a specified point, a region in which zero forces are outputon the knob. Thus, the curve 138 shown in FIG. 7a shows a detent forcestarting at a magnitude M1 at location P1 and, when the knob is movedtoward the origin O, the force increases to the maximum point M2 atlocation P2 and then decreases until point P3, where the deadband isreached (zero magnitude). Similarly, at point P14 on the other side ofthe origin O, the force increases from zero to a maximum magnitude M5 atlocation P5, after which the force drops a short distance to magnitudeM6 at location P6. The force then drops to zero for increasing d, untilanother detent effect is encountered. The small decreases in forcemagnitude from the maximum magnitude at the end points of the curve 138are useful in some detent embodiments to provide a less extremeassistive or resistive force to the user when entering or exiting thedetent range, e.g., to gradually lead the user into the detent rangebefore outputting the maximum force. This can provide a smoother-feelingand, in some cases, a more easily-selected detent (i.e., it can beeasier to position the knob at the detent's origin).

[0077] The detent curve 138 can thus be defined using the parametersshown in FIG. 7a. For example, a force command protocol can provide anumber of different commands that can cause the output of differentforce sensations to the user. The commands can each include a commandidentifier followed by one or more command parameters that define andcharacterize the desired force sensation. An example of a commanddefining a detent curve 138 is as follows:

[0078] DETENT (TYPE, PERIOD, MAGNITUDE, LOCATION, DEADBAND, FLAG, WIDTH,PHASE, OFFSET, LOCATION, INCREMENT, ARRAY POINTER)

[0079] The DETENT identifier indicates the type of force sensation. TheTYPE parameter indicates a type of periodic wave from which to base theforce detent curve, such as a sine wave, triangle wave, square wave,ramp, etc. The PERIOD and MAGNITUDE parameters define thosecharacteristics of the periodic wave. The LOCATION parameter defines thelocation of the origin position for the detent in the degree of freedomof the knob. The DEADBAND parameter indicates the size of the deadbandaround the origin position. The FLAG parameter is a flag that indicateswhether the detent is provided on the positive side, the negative side,or both sides around the location (origin position). The WIDTH parameterdefines the amount of the wave 139 used for the detent curve, i.e. theextent of the wave used starting from the PHASE position. The PHASEparameter indicates the starting position of the detent curve 138 on thewave 139 (and is described in greater detail below). The OFFSETparameter indicates the amount of magnitude offset that curve 138includes from the d axis, and is described in greater detail below. TheINCREMENT parameter indicates the distance in the degree of freedom ofthe knob between successive detent locations. The optional LOCATIONARRAY POINTER parameter indicates a location in a separate array thathas been previously programmed with the particular positions in thedegree of freedom of the knob at which the detents are located and(optionally) the total number of detents; the array can be provided inmemory, such as RAM, or other writable storage device. For example, thearray can be preprogrammed with three detents, at locations of 45degrees, 78 degrees, and 131 degrees in the rotation of the knob. Thearray can be accessed is necessary to retrieve these locations at whichdetent forces are to be output. This can be useful when the detentlocations are not evenly or regularly spaced in the degree of freedom,and/or when a particular number of detents is desired to be output.

[0080] Furthermore, in other embodiments, a periodic wave can beadditionally “shaped” to form a particular detent curve. For example, an“envelope” can be applied to a periodic wave to shape the wave in aparticular way. One method of shaping a wave is to define a firstmagnitude and a settle width, which is the distance required for thewave to settle to a second, lesser magnitude from the first magnitude.This settle width thus provides a ramping shape to the upper and/orlower portions of the periodic wave about axis d. Although such shapingis performed in a spatial domain, it is similar to the force signalshaping in the time domain described in co-pending U.S. patentapplication Ser. No. 08/747,841, incorporated herein by reference. Suchshaping is also described in co-pending U.S. patent application Ser.Nos. 08/846,011 and 08/877,114, incorporated herein by reference. Theshaping can be specified by parameters in a commands, such as a settledwidth parameter, magnitude parameters, etc.

[0081] The detent command can be sent by a supervisory microprocessor toa lower-level local microprocessor to decode and interpret the commandsto control procedures provided in device 10 in firmware or other storagemedium, as described with reference to FIG. 8 below. If a host computerand local microprocessor are used, the host computer can send thecommand to the local microprocessor, which parses/decodes and interpretsthe command and causes appropriate forces to be output. Commands andprotocols for use in force feedback are described in greater detail inU.S. Pat. No. 5,734,373, incorporated by reference herein. Such commandscan also be retrieved from a storage device such as memory and thenparsed and interpreted by a local microprocessor.

[0082] The ability to define a force detent (in the spatial domain) interms of a periodic waveform can be useful in force feedbackimplementations in which periodic force effects in the time domain arealso provided. For example, vibration force sensations can be providedby outputting a periodic sine wave or square wave for the magnitude ofthe force over time. If such time-based effects can be output on knob 18or 34, then it is convenient to use the same periodic wave definitionsand data for defining force vs. position profiles for detents as shownin FIGS. 7a-7 e.

[0083]FIG. 7b is a graph illustration 140 showing particular parametersof the detent command described above which are applied to a periodicwave. Sine wave 142 has a magnitude and period as shown. A specifiedphase of the desired detent curve causes the detent curve to start at aposition on wave 142 in accordance with the phase. For example, in FIG.7b, a phase of 50 degrees is specified. This will cause the resultingdetent curve to start at point P on the wave 142. A width parameterspecifics the amount of the wave from the phase location to be used asthe detent curve. Furthermore, an offset of −0.8 is indicated. Thiscauses the resulting detent curve to be shifted down by 80% from thewave 142. Furthermore, a deadband is also specified (not shown in FIG.7b.).

[0084]FIG. 7c is a graph 144 showing the resulting detent curve 146obtained from the application of the parameters to the wave 142described with reference to FIG. 7b. The portion of the wave 142starting at the phase and positioned above the offset line in FIG. 7b isused in the detent curve 146. Furthermore, a deadband 148 has been addedto the curve. The flag in the detent command has caused the positiveside of the curve 146 to be mirrored on the negative side of the originO. This detent curve 146 causes a detent force that is similar to thedetent force described with reference to FIG. 7a, only smaller inmagnitude and in position range over the degree of freedom of the knob.

[0085]FIG. 7d is a graph 160 showing a periodic wave and parameters tobe applied to the wave. Sine wave 162 is provided as described above,having a particular period and magnitude. An offset is specified for theresulting detent curve; in the example of FIG. 7d, the offset is 1, thuscausing the detent curve to be shifted upward by its entire magnitude. Aphase of 270 degrees is also indicated, so that the detent curve startsat the lowest magnitude of the wave 172 at point P. Furthermore, anincrement is also specified as a parameter (not shown). FIG. 7e is agraph 170 illustrating the detent curves 172 and 174 resulting from thewave 162 and parameters described with reference to FIG. 7d. The portionof the wave 162 past point P and ending at a point defined by a widthparameter is provided both on the positive side and the negative side oforigin O1 of graph 170 for curve 172 (the positive and negagtive sidesare designated by the flag parameter). A second curve 174 is also shown,where the origin O2 of the second curve is positioned at a distance fromthe origin O1 as specified by the increment parameter. Additional curvessimilar to curves 172 and 174 are provided at further distances at sameincrement from each other. The detent curves 172 and 174 provide a muchsteeper, less gradual detent force over the detent range than the otherdetent forces shown in FIGS. 7a and 7 c. Furthermore, no actual deadbandis specified, although the shape or each half of the curve 172 providesa small zone 176 where zero force is output, similar to a deadband.

[0086]FIG. 8 is a block diagram illustrating an electromechanical system200 for the device 10 of FIG. 1 suitable for use with the presentinvention. A force feedback system including many of the belowcomponents is described in detail in co-pending patent application Ser.No. 09/049,155, filed Mar. 26, 1998, and U.S. Pat. No. 5,734,373, whichare both incorporated by reference herein in their entirety.

[0087] In one embodiment, device 10 includes an electronic portionhaving a local microprocessor 202, local clock 204, local memory 206,sensor interface 208, and actuator interface 210.

[0088] Local microprocessor 202 is considered “local” to device 10,where “local” herein refers to processor 202 being a separatemicroprocessor from any other microprocessors, such as in a controllinghost computer (see below), and refers to processor 202 being dedicatedto force feedback and/or sensor I/O for the knob 18 of the interfacedevice 10. In force feedback embodiments, the microprocessor 202 readssensor signals and can calculate appropriate forces from those sensorsignals, time signals, and force processes selected in accordance with ahost command, and output appropriate control signals to the actuator.Suitable microprocessors for use as local microprocessor 202 include the8X930AX by Intel, the MC68HC711E9 by Motorola and the PIC16C74 byMicrochip, for example. Microprocessor 202 can include onemicroprocessor chip, or multiple processors and/or co-processor chips,and can include digital signal processor (DSP) functionality. Also,“haptic accelerator” chips can be provided which are dedicated tocalculating velocity, acceleration, and/or other force-related data.Alternatively, fixed digital logic and/or state machines can be used toprovide similar functionality.

[0089] A local clock 204 can be coupled to the microprocessor 202 toprovide tilling data, for example, to compute forces to be output byactuator 70. In alternate embodiments using the USB communicationinterface, timing data for microprocessor 202 can be retrieved from theUSB interface. Local memory 206, such as RAM and/or ROM, is preferablycoupled to microprocessor 202 in interface device 10 to storeinstructions for microprocessor 202, temporary and other data,calibration parameters, adjustments to compensate for sensor variationscan be included, and/or the state of the device 10. Display 14 can becoupled to local microprocessor 202 in some embodiments. Alternatively,a different microprocessor or other controller can control output to thedisplay 14.

[0090] Sensor interface 208 may optionally be included in device 10 toconvert sensors signals to signals that can be interpreted by themicroprocessor 202. For example, sensor interface 208 can receivesignals from a digital sensor such as an encoder and convert the signalsinto a digital binary number. An analog to digital converter (ADC) canalso be used. Such circuits, or equivalent circuits, are well known tothose skilled in the art. Alternately, microprocessor 202 can performthese interface functions. Actuator interface 210 can be optionallyconnected between the actuator 70 and microprocessor 202 to convertsignals from microprocessor 202 into signals appropriate to drive theactuators. Actuator interface 210 can include power amplifiers,switches, digital to analog controllers (DACs), and other components, aswell known to those skilled in the art. In alternate embodiments,actuator interface 210 circuitry can be provided within microprocessor202 or in the actuator 70.

[0091] A power supply 212 can be coupled to actuator 70 and/or actuatorinterface 210 to provide electrical power. In a different embodiment,power can be supplied to the actuator 70 and any other components (asrequired) by an interface bus. Power can also be stored and regulated bydevice 10 and thus used when needed to drive actuator 70.

[0092] A mechanical portion is included in device 10, an example ofwhich is shown above in FIGS. 3a-3 b and 4 a-4 c. The mechanical portioncan include some or all of the components needed for rotational motionof knob 18, transverse motion of knob 18, the push and/or pull motion ofknob 18, and force feedback in any or all of these degrees of freedom ofthe knob.

[0093] Mechanical portion 200 preferably includes sensors 214, actuator70, and mechanism 216. Sensors 214 sense the position, motion, and/orother characteristics of knob 18 along one or more degrees of freedomand provide signals to microprocessor 202 including informationrepresentative of those characteristics. Typically, a sensor 214 isprovided for each degree of freedom along which knob 18 can be moved,or, a single compound sensor can be used for multiple degrees offreedom. Sensors 214 can include sensor 76, switch 52, and switch 58 asshown in FIGS. 3a-3 b. For example, one switch 52 of FIGS. 3a-3 b orswitch 90 of FIG. 4c can include a sensor switch for each transversedirection 28 that the knob 18 can be moved. Examples of sensors suitablefor rotary sensor 70 of FIGS. 3a-3 b and 4 a-4 c include opticalencoders, analog sensors such as potentiometers, Hall effect magneticsensors, optical sensors such as a lateral effect photo diodes,tachometers, and accelerometers. Furthermore, both absolute and relativesensors may be used.

[0094] In those embodiments including force feedback, actuator 70transmits forces to knob 18 in one or more directions in a rotary degreeof freedom in response to signals output by microprocessor 202 or otherelectronic logic or device, i.e., it is “electronically-controlled.” Theactuator 70 produces electronically modulated forces which means thatmicroprocessor 202 or other electronic device controls the applicationof the forces. Typically, an actuator 70 is provided for each knob 18that includes force feedback functionality. In some embodiments,additional actuators can also be provided for the other degrees offreedom of knob 18, such as the transverse motion of the knob 18 and/orthe push or pull motion of the knob. The actuators, such as actuator 70,can include active actuators, such as linear current control motors,stepper motors, pneumatic/hydraulic active actuators, a torquer (motorwith limited angular range), voice coil actuators, etc. Passiveactuators can also be used, including magnetic particle brakes, frictionbrakes, or pneumatic/hydraulic passive actuators, and generate a dampingresistance or friction in a degree of motion. In some embodiments, allor some of sensors 214 and actuator 70 can be included together as asensor/actuator pair transducer, as shown in FIGS. 3a-3 b for actuator70 and sensor 76.

[0095] Mechanism 216 is used to translate motion of knob 18 to a formthat can be read by sensors 214, and, in those embodiments includingforce feedback, to transmit forces from actuator 70 to knob 18. Examplesof mechanism 216 are shown with respect to FIGS. 3a-3 h and 4 a-4 c.Other types of mechanisms can also be used, as disclosed in U.S. Pat.Nos. 5,767,839, 5,721,566, 5,805,140, and co-pending patent applicationSer. Nos. 08/664,086, 08/709,012, and 08/736,161, all incorporated byreference herein.

[0096] Also, a drive mechanism such as a capstan drive mechanism can beused to provide mechanical advantage to the forces output by actuator70. Some examples of capstan drive mechanisms are described in U.S. Pat.No. 5,731,804 and co-pending patent application Ser. Nos. 08/961,790,08/736,161, all incorporated by reference herein. Alternatively, a beltdrive system, gear system, or other mechanicalamplification/transmission system can be used.

[0097] Other input devices 220 can be included in interface device 10and send input signals to microprocessor 202. Such input devices caninclude buttons, such as buttons 16 on front panel 12 as shown in FIG.1, used to supplement the input from the knob to the device 10. Also,dials, switches, voice recognition hardware (e.g. a microphone, withsoftware implemented by microprocessor 202), or other input mechanismscan be used, can also be included to send a signal (or cease sending asignal) to microprocessor 202 or to the actuator 70 or actuatorinterface 210, indicating that the user is not gripping the knob 18, atwhich point all output forces are ceased for safety purposes. Suchsafety switches are described in U.S. Pat. No. 5,691,898 incorporated byreference herein.

[0098] Furthermore, a safety or “deadman” switch 222 can optionally beincluded for the knob 18 in those implementations providing forcefeedback on the knob. The safety switch prevents forces from beingoutput on the knob when the user is not contacting or using it, and toprevent the knob from spinning on its own when the user is not touchingit. In one embodiment, the safety switch detects contact of a user'sdigit (finger, thumb, etc.) with the knob 18. Such a switch can beimplemented as a capacitive sensor or resistive sensor, the operation ofwhich is well known to those skilled in the art. In a differentembodiment, a switch or sensor that detects pressure on the knob 18 fromthe user can be used. For example, a switch can be sensitive to apredetermined amount of pressure, which will close the switch.Alternatively, a pressure magnitude sensor can be used as the safetyswitch, where forces are output on the knob only when a pressuremagnitude over a minimum threshold is sensed. A pressure requirement forsafety switch 222 has the advantage of ensuring good contact betweenfinger and knob before forces are Output; output forces are enabled onlywhen the user is moving or actively using the knob. Thus, if the usersimply rests his or her finger lightly on the knob without intending touse it, no forces will be output to surprise the user.

[0099] Other microprocessor 224 can be included in some embodiments tocommunicate with local microprocessor 202. Microprocessors 202 and 224are preferably coupled together by a bi-directional bus 226. Additionalelectronic components may also be included for communicating viastandard protocols on bus 226. These components can be included indevice 10 or another connected device. Bus 226 can be any of a varietyof different communication busses. For example, a bi-directional serialor parallel bus, a wireless link, a network architecture (such asCanbus), or a uni-directional bus can be provided betweenmicroprocessors 224 and 202.

[0100] Other microprocessor 224 can be a separate microprocessor in adifferent device or system that coordinates operations or functions withthe device 10. For example, other microprocessor 224 can be provided ina separate control subsystem in a vehicle or house, where the othermicroprocessor controls the temperature system in the car or house, orthe position of mechanical components (car mirrors, seats, garage door,etc.), or a central display device that displays information fromvarious systems. Or, the other microprocessor 224 can be a centralizedcontroller for many systems including device 10. The two microprocessors202 and 224 can exchange information as needed to facilitate control ofvarious systems, output event notifications to the user, etc. Forexample, if other microprocessor 224 has determined that the vehicle isoverheating, the other microprocessor 224 can communicate thisinformation to the local microprocessor 202, which then can output aparticular indicator on display 14 to warn the user. Or, if the knob 18is allowed different modes of control, the other microprocessor 224 cancontrol a different mode. Thus, if the knob 18 is able to control bothaudio stereo output as well as perform temperature control, the localmicroprocessor 202 can handle audio functions but can pass all knobsensor data to other microprocessor 224 to control temperature systemadjustments when the device 10 is in temperature control mode.

[0101] In other embodiments, other microprocessor 224 can be amicroprocessor in a host computer, for example, that commands the localmicroprocessor 202 to output force sensations by sending host commandsto the local microprocessor. The host computer can be a personalcomputer, workstation, video game console, or other computing or displaydevice, set top box, “network-computer”, etc. Besides microprocessor224, the host computer preferably includes random access memory (RAM),read only memory (ROM), input/output (I/O) circuitry, and othercomponents of computers well-known to those skilled in the art. The hostcomputer can implement a host application program with which a userinteracts using knob 18 and/or other controls and peripherals. The hostapplication program can be responsive to signals from knob 18 such asthe transverse motion of the knob, the push or pull motion, and therotation of the knob (e.g., the knob 18 can be provided on a gamecontroller or interface device such as a game pad, joystick, steeringwheel, or mouse that is connected to the host computer). In forcefeedback embodiments, the host application program can output forcefeedback commands to the local microprocessor 202 and to the knob 18. Ina host computer embodiment or other similar embodiment, microprocessor202 can be provided with software instructions to wait for commands orrequests from the host computer, parse/decode the command or request,and handle/control input and output signals according to the command orrequest.

[0102] For example, in one force feedback embodiment, hostmicroprocessor 224 can provide low-level force commands over bus 226,which microprocessor 202 directly transmits to the actuators. In adifferent force feedback local control embodiment, host microprocessor224 provides high level supervisory commands to microprocessor 202 overbus 226, and microprocessor 202 manages low level force control loops tosensors and actuators in accordance with the high level commands andindependently of the host computer. In the local control embodiment, themicroprocessor 202 can independently process sensor signals to determineappropriate output actuator signals by following the instructions of a“force process” that may be stored in local memory 206 and independentlycalculation instructions, formulas, force magnitudes (force profiles),and/or other data. The force process can command distinct forcesensations, such as vibrations, textures, jolts, or even simulatedinteractions between displayed objects. Such operation of localmicroprocessor in force feedback applications is described in greaterdetail in U.S. Pat. No. 5,734,373, previously incorporated herein byreference.

[0103] In an alternate embodiment, no local microprocessor 202 isincluded in interface device 10, and a remote microprocessor, such asmicroprocessor 224, controls and processes all signals to and from thecomponents of interface device 10. Or, hardwired digital logic canperform any input/output functions to the knob 18.

[0104] While this invention has been described in terms of severalpreferred embodiments, there are alterations, modifications, andpermutations thereof which fall within the scope of this invention. Itshould also be noted that the embodiments described above can becombined in various ways in a particular implementation. Furthermore,certain terminology has been used for the purposes of descriptiveclarity, and not to limit the present invention. It is thereforeintended that the following appended claims include such alterations,modifications, and permutations as fall within the true spirit and scopeof the present invention.

1. A knob controller device comprising: a knob coupled to a groundedsurface, said knob rotatable in a rotary degree of freedom about an axisextending through said knob, said knob also moveable in it transversedirection approximately perpendicular to said axis; a rotational sensorthat detects a position of said knob in said rotary degree of freedom; atransverse sensor operative to detect a position of said knob in saidtransverse direction; and an actuator coupled to said knob and operativeto output a force in said rotary degree of freedom about said axis.
 2. Aknob controller device as recited in claim 1 wherein said knob is alsomoveable in a linear degree of freedom approximately parallel to saidaxis, and further comprising a linear sensor operative to detect aposition of said knob in said linear degree of freedom.
 3. A knobcontroller device as recited in claim 2 wherein said knob can be pushedby a user, said pushing motion being detected by said linear sensor. 4.A knob controller device as recited in claim 2 wherein said knob can bepulled by a user, said pulling motion being detected by said linearsensor.
 5. A knob controller device as recited in claim 1 wherein saidknob is moveable in a plurality of transverse directions, and whereinsaid transverse sensor is operative to detect when said knob is moved inany of said transverse directions.
 6. A knob controller device asrecited in claim 1 wherein said transverse sensor includes a hat switchhaving a plurality of individual switches, each of said individualswitches detecting movement of said knob in a particular transversedirection.
 7. A knob controller device as recited in claim 6 whereinsaid knob is moveable in four transverse directions spaced approximatelyorthogonal to each other, and wherein said hat switch includes fourindividual switches.
 8. A knob controller device as recited in claim 1further comprising a microprocessor coupled to said rotational sensorand to said transverse sensor, said microprocessor receiving sensorsignals from said sensors and controlling a function of a device inresponse to said sensor signals.
 9. A knob controller device as recitedin claim 8 wherein said device is an audio device.
 10. A knob controllerdevice as recited in claim 1 further comprising a microprocessor coupledto said rotational sensor and to said transverse sensor, saidmicroprocessor receiving sensor signals from said sensors andcontrolling a function of a device in response to said sensor signals,said microprocessor sending force feedback signals to said actuator tocontrol forces output by said actuator.
 11. A knob controller device isrecited in claim 1 further comprising a display, wherein an image onsaid display is changed in response to manipulation of said knob in saidtransverse direction.
 12. A knob controller device as recited in claim 1wherein a flexible member is coupled between said knob and said actuatorto allow said movement in said tranverse direction.
 13. A knobcontroller device as recited in claim 12 wherein said flexible member isa spring member.
 14. A knob controller device as recited in claim 12wherein said flexible member includes a base plate and a plurality ofbent flexible portions coupled to said base plate.
 15. A knob controllerdevice comprising: a knob coupled to a grounded surface, said knobrotatable in a rotary degree of freedom about an axis extending throughsaid knob, said knob also moveable in a linear degree of freedomapproximately parallel to said axis; a rotational sensor that detects aposition of said knob in said rotary degree of freedom; a linear sensorthat detects a position of said knob in said linear degree of freedom;and an actuator coupled to said knob and operative to output a force insaid rotary degree of freedom about said axis.
 16. A knob controllerdevice as recited in claim 15 further comprising a microprocessorcoupled to said rotational sensor and to said linear sensor, saidmicroprocessor receiving sensor signals from said sensors andcontrolling a function of a device in response to said sensor signals,said microprocessor sending force feedback signals to said actuator tocontrol forces output by said actuator.
 17. A knob controller device asrecited in claim 15 wherein said knob can be pushed by a user, saidpushing motion being detected by said linear sensor.
 18. A knobcontroller device as recited in claim 15 wherein said knob can be pulledby a user, said pulling motion being detected by said linear sensor. 19.A knob controller device as recited in claim 15 wherein said knob can bepushed or pulled by a user, said pushing motion and said pulling motionbeing detected by said linear sensor.
 20. A knob controller device asrecited in claim 15 said knob is also moveable in a plurality oftransverse directions approximately perpendicular to said axis, andfurther comprising a transverse sensor operative to detect movement ofsaid knob in any of said transverse directions.
 21. A knob controllerdevice as recited in claim 15 further comprising a spring member forbiasing said knob to a center position in said linear degree of freedom.22. A knob controller device as recited in claim 15 wherein said linealsensor includes a grounded switch that is contacted by a pusher membercoupled to said knob when said knob is moved in said linear degree offreedom.
 23. A knob controller device as recited in claim 15 whereinsaid linear sensor detects a position of said knob within a detectablecontinuous range of motion of said knob, and wherein said linear sensoroutputs a sensor signal indicative of said position.
 24. A method forcontrolling functions of a device from input provided by a knob, themethod comprising: reading a rotary sensor signal from a rotary sensor,said rotary sensor signal being representative of a position of a knobin a rotary degree of freedom about an axis extending through said knob;reading a transverse switch signal from a transverse switch, saidtransverse switch signal indicating when said knob is moved in atransverse degree of freedom approximately perpendicular to said axis;using at least one of said rotary sensor signal and said transverseswitch signal to control at least one function of said device; andproviding a force feedback signal to an actuator that is coupled to saidknob, said force feedback signal being based at least in part on saidrotary sensor signal.
 25. A method as recited in claim 24 furthercomprising reading a linear sensor signal from a linear sensor, saidlinear sensor signal being representative of a position of said knob ina linear degree of freedom approximately parallel to said axis.
 26. Amethod as recited in claim 25 wherein said function of said deviceincludes at least one of adjusting a frequency of a radio tuner,adjusting a temperature in an area and controlling a physical positionof a mechanical component.
 27. A method as recited in claim 24 whereinsaid function of said device includes adjusting a displayed image basedon at least one said rotary sensor signal and said transverse switchsignal.
 28. An interface control device including force feedback andproviding rate control and position control modes, the interface controldevice comprising: a user manipulatable object grasped by a user andmovable in a degree of freedom; an actuator coupled to said usermanipulatable object and providing forces on said user manipulatableobject in said degree of freedom; a sensor that detects a position ofsaid user manipulatable object in said degree of freedom and outputs asensor signal including information representing said position; amicroprocessor coupled to said actuator and to said sensor, saidmicroprocessor controlling said forces provided by said actuator andreceiving said sensor signal from said sensor, wherein saidmicroprocessor commands either a position control mode or a rate controlmode for said user manipulatable object, wherein said position controlmode controls a value based on a position of said user manipulatableobject in said degree of freedom, and wherein said rate control modecontrols a rate of change of said value based on a position of said usermanipulatable object in said degree of freedom.
 29. An interface controldevice as recited in claim 28 wherein said degree or freedom is a rotarydegree of freedom, and wherein said user manipulatable object includes arotary knob.
 30. An interface control device as recited in claim 28wherein said degree of freedom is a linear degree of freedom, andwherein said user manipulatable object includes a slider control knob.31. An interface control device as recited in claim 28 wherein said ratecontrol mode provides a force on said user manipulatable object usingsaid actuator, said force being applied in a direction opposing amovement of said user manipulatable object away from an origin position.32. An interface control device as recited in claim 28 wherein saidforce opposing said movement is a spring force.
 33. An interface controldevice as recited in claim 28 wherein said microprocessor controls saidactuator to output at least one force detent during movement of saidknob in said position control mode.
 34. An interface control device asrecited in claim 28 wherein said rate of change is related to adisplacement of said user manipulatable with respect to an originposition.
 35. An interface control device as recited in claim 28 whereinsaid rate control mode is used to control the value of a volume, bass,treble, or balance function of said device.
 36. An interface controldevice as recited in claim 28 wherein said position control mode is usedto control the value of a volume, bass, treble, or balance function ofsaid device.
 37. An interface control device as recited in claim 28wherein said rate control mode is used to control a position of aphysical component in a vehicle.
 38. A method for providing detentforces for a force feedback control, the method comprising: outputting afirst force for a first detent on a user manipulatable object contactedby a user and moveable in a degree of freedom, said first force beingoutput when said user manipulatable object is moved within a range ofsaid first detent, said first force being output by aelectronically-controlled actuator, wherein said first force assistsmovement of said user manipulatable object toward an origin position ofsaid first detent and wherein said first force resists movement of saiduser manipulatable object away from said origin position of said firstdetent; and outputting a second force for a second detent on said usermanipulatable object when said user manipulatable object is moved withina range of said second detent, said second force being output by saidactuator and said second detent having an origin position different fromsaid origin position of said first detent, wherein said second forceassists movement of said user manipulatable object toward an originposition of said second detent and wherein said second force resistsmovement of said user manipulatable object away from said originposition of said second detent, wherein a portion of said range of saidfirst detent overlaps a portion of said range of said second detent. 39.A method as recited in claim 38 wherein said first force for said firstdetent has a magnitude that increases the further that said usermanipulatable object is positioned from said origin of said firstdetent, and wherein said second force for said second detent has amagnitude that increases the further that said user manipulatable objectis positioned from said origin of said second detent.
 40. A method asrecited in claim 38 wherein a deadband is provided around said origin ofsaid first detent and around said origin of said second detent, whereina magnitude of said first force and said second force is zero when saiduser manipulatable object is positioned within said deadband.
 41. Amethod as recited in claim 38 wherein when said user manipulatableobject is moved in a particular direction from said first detent to saidsecond detent, said first detent range has an endpoint positioned aftera beginning point of said second detent range such that a force at saidbeginning point of said second detent range has less magnitude than aforce at an endpoint of said second detent range.
 42. A method asrecited in claim 41 wherein when said user manipulatable object is movedin a direction opposite to said particular direction from said seconddetent to said first detent, a force at a first-encountered point ofsaid first detent range has less magnitude than a force at alast-encountered point of said first detent range.
 43. A method asrecited in claim 41 wherein said first detent range does not overlappast said origin of said second detent.
 44. A method as recited in claim38 wherein said user manipulatable object is a knob and said degree offreedom is a rotary degree of freedom.
 45. A method for providing detentforces for a force feedback control, the method comprising: defining aperiodic wave; using at least a portion of said periodic wave to definea detent force curve, said detent force curve defining a force to beoutput on a user manipulatable object based on a position of said usermanipulatable object in a degree of freedom, said user manipulatableobject being contacted and moveable by a user; and using said detentforce curve to command said force on said user manipulatable object,said force being output by a electronically-controlled actuator.
 46. Amethod as recited in claim 45 wherein said defining a periodic waveincludes specifying a type, a period and a magnitude for said periodicwave.
 47. A method as recited in claim 45 wherein said using at least aportion of said periodic wave to define a detent force curve includesspecifying a portion of said periodic wave to define a width of saiddetent force curve.
 48. A method as recited in claim 47 wherein saidusing at least a portion of said periodic wave to define a detent forcecurve includes specifying a phase and an offset to be applied to saidperiodic wave to define said detent force curve.
 49. A method as recitedin claim 45 wherein said using at least a portion of said periodic waveto define a detent force curve includes specifying an incrementdistance, wherein successive detent force curves in said degree offreedom are spaced apart by said increment distance.
 50. A method asrecited in claim 45 wherein said user manipulatable object is a knobmoveable in a rotary degree of freedom.